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Ratio
Question 196 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
If m : n = 3 : 2, then (4m + 5n) : (4n - 5n) is equal to =?
11 : 1 | |
4 : 9 | |
9 : 4 | |
9 : 1 |
Question 196 Explanation:
\begin{align} & m:n = 3:2 \cr & \frac{m}{n} = \frac{3}{2} \cr & \Rightarrow \frac{{4m + 5n}}{{4m - 5n}} \cr & \Rightarrow \frac{{n\left( {4\frac{m}{n} + 5} \right)}}{{n\left( {4\frac{m}{n} - 5} \right)}} \cr & \Rightarrow \frac{{4 \times \frac{3}{2} + 5}}{{4 \times \frac{3}{2} - 5}} \cr & \Rightarrow \frac{{6 + 5}}{{6 - 5}} \cr & \Rightarrow \frac{{11}}{1} \cr & \Rightarrow 11:1 \cr\end{align}
Question 197 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
If x : y = 3 : 4, then the value of (4x - y) : (2x + 3y) is =?
4 : 9 | |
8 : 3 | |
4 : 3 | |
8 : 9 |
Question 197 Explanation:
\begin{align} & x:y = 3:4 \cr & \therefore \frac{x}{y} = \frac{3}{4} \cr & \Rightarrow \frac{{4x - y}}{{2x + 3y}} \cr & \Rightarrow \frac{{y\left( {4\frac{x}{y} - 1} \right)}}{{y\left( {2\frac{x}{y} + 3} \right)}} \cr & \Rightarrow \frac{{4 \times \frac{3}{4} - 1}}{{2 \times \frac{3}{4} + 3}} \cr & \Rightarrow \frac{{\left( {3 - 1} \right) \times 2}}{{3 + 6}} \cr & \Rightarrow \frac{4}{9} \cr & \Rightarrow 4:9 \cr\end{align}
Question 198 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
Two alloys contain tin and iron in the ratio of 1 : 2 and 2 : 3. If the two alloys are mixed in the proportion of 3 : 4 respectively (by weight), the ratio of tin and iron in the newly formed alloy is =?
12 : 23 | |
13 : 22 | |
14 : 25 | |
10 : 21 |
Question 198 Explanation:
According to the question,
| Sn | : | Fe |
| A → 1 | : | 2 = 3) $\times$ 5 |
| B → 2 | : | 3 = 5)$\times$3 |
Question 199 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
25% of A's income is equal to 35% of B's income. The ratio of the incomes of A and B is -
7 : 5 | |
13 : 15 | |
15 : 13 | |
5 : 7 |
Question 199 Explanation:
\begin{align} & = {\text{25}}\% {\text{ of A}} = {\text{35}}\% {\text{ of B}} \cr & \Rightarrow \frac{{25}}{{100}}{\text{A}} = \frac{{35}}{{100}}{\text{B}} \cr & \Rightarrow \frac{{\text{A}}}{4} = \frac{{7{\text{B}}}}{{20}} \cr & \Rightarrow \frac{{\text{A}}}{{\text{B}}} = \frac{7}{{20}} \times 4 = \frac{7}{5} \cr & \Rightarrow {\text{A}}:{\text{B}} = 7:5. \cr\end{align}
Question 200 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
If (a + b) : (b + c) : (c + a) and (a + b + c) = 14, then the value of c is =?
8 | |
6 | |
14 | |
7 |
Question 200 Explanation:
(a + b) : (b + c) : (c + a)
6 : 7 : 8
Le t 6x : 7x : 8x
∴ a + b + b + c + a = 6x + 7x + 8x \begin{align} & \Rightarrow 2a + 2b + 2c = 21x \cr & \Rightarrow 2\left( {a + b + c} \right) = 21x \cr & \Rightarrow a + b + c = \frac{{21}}{2}x \cr & \Rightarrow a + b + c = 14{\text{ given}} \cr & \Rightarrow \frac{{21x}}{2} = 14 \cr & \Rightarrow x = \frac{{28}}{{21}} = \frac{4}{3} \cr & \therefore a + b = 6 \times \frac{4}{3} = 8 \cr & \therefore a + b + c = 14 \cr & \Rightarrow 8 + c = 14 \cr & \Rightarrow c = 14 - 8 = 6 \cr\end{align}
There are 200 questions to complete.